feat: per-album hero image – picker from album assets, fullbleed banner on detail page

app/api/admin/albums/[albumId]/assets/route.ts

@@ -0,0 +1,66 @@
+/**
+ * Admin API: Get assets of a specific album for the hero image picker.
+ */
+
+import { NextRequest, NextResponse } from 'next/server';
+import { isAdminAuthenticated, isAdminEnabled } from '@/lib/admin/auth';
+import { getConfig } from '@/lib/config';
+
+interface ImmichAlbumDetail {
+  assets: Array<{
+    id: string;
+    type: string;
+    originalFileName: string;
+    thumbhash: string | null;
+    fileCreatedAt: string;
+    isFavorite: boolean;
+  }>;
+}
+
+export async function GET(
+  _request: NextRequest,
+  { params }: { params: Promise<{ albumId: string }> },
+) {
+  if (!isAdminEnabled()) {
+    return NextResponse.json({ error: 'Admin not enabled' }, { status: 403 });
+  }
+  if (!(await isAdminAuthenticated())) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
+  }
+
+  const config = getConfig();
+  if (config.needsSetup) {
+    return NextResponse.json({ error: 'Immich not configured' }, { status: 503 });
+  }
+
+  const { albumId } = await params;
+
+  try {
+    const res = await fetch(`${config.immich.apiUrl}/albums/${albumId}`, {
+      headers: {
+        'x-api-key': config.immich.apiKey,
+        Accept: 'application/json',
+      },
+    });
+
+    if (!res.ok) {
+      return NextResponse.json({ error: `Immich API returned ${res.status}` }, { status: 502 });
+    }
+
+    const album = (await res.json()) as ImmichAlbumDetail;
+
+    const assets = album.assets
+      .filter((a) => a.type === 'IMAGE')
+      .map((a) => ({
+        id: a.id,
+        originalFileName: a.originalFileName,
+        fileCreatedAt: a.fileCreatedAt,
+        isFavorite: a.isFavorite,
+      }));
+
+    return NextResponse.json({ assets, nextPage: null });
+  } catch (err) {
+    console.error('Failed to fetch album assets:', err);
+    return NextResponse.json({ error: 'Failed to fetch album assets' }, { status: 500 });
+  }
+}